Article

Accelerometry has been recognized as a method of objectively measuring community
ambulation in persons with multiple sclerosis (MS).
However, the assumption that
walking itself serves as a major contributor to the accelerometer signal has yet
to be tested. This study examined the assumption that community-based walking is
a primary contributor to accelerometer output in MS. Ambulatory persons (5
males/17 females; 13 without aid/9 with aid) with MS wore a triaxial
accelerometer (ActiGraph GT3X, Health One Technologies; Fort Walton Beach,
Florida) as well as an IDEEA system (MiniSun, Inc; Fresno, Florida) over the
course of a single day. Outcome measures for the accelerometer included movement
counts/hour for the vertical, anterior-posterior, and mediolateral axes. Outcomes
for the IDEEA system included percent time walking, sitting, and standing, as
well as walking speed. Pearson product correlations (r) were used to examine the
associations between outcomes from the accelerometer and IDEEA system.
Significant correlations were observed between percent walking time and movement
counts/hour along the vertical (r = 0.84) and anterior-posterior (r = 0.69) axes.
Significant correlations were further noted between movement counts/hour along
the vertical axis and walking speed (r = 0.45) and self-report walking impairment
(r = -0.50) and disability (r = -0.46). Such observations further support
accelerometry as an objective marker of community ambulation in persons with MS.

Langue : ANGLAIS